Introduction

The presented solution is a new method for the simultaneous detection of multiple analytes in a liquid. A set of micro-chambers with a plurality of biosensors within is operated under pulsating flow mode, ensuring the same liquid flow per channel. A prototype has been successfully tested for in situ analysis of pollutants in seawater.

Technical features

The proposed solution is a new method to assure the same amount of flow per channel within a multi-analyte biosensors device. With this measuring approach,the micro-chambers containing the respective biosensors are flooded cyclically, one at a time,with a pulsing liquid flow through sequentially temporized micro-valves. This liquid subdivision (multiplexing) is driven by a microprocessor firmware controlling the opening/closing of the micro valves according  to analytes and biosensors requirements. Pulsing flow mode, as opposed to continuous flow, exhibits the advantage of alternating turbulent and rest regimes in the micro-chamber allowing a much better efficiency of the functional liquid during typical biosensors operations such as antigens accumulation, electrodes washing and regeneration. Turbulence favours a true contact of the functional liquid with biosensor electrodes, counteracting typical surface effects arising in continuous, constant low- rate flow which almost prevent liquid circulation at biosensor electrodes surface.

Possible Applications

• In-situ biosensor devices that monitor sea / river / freshwater pollutants or quality;
• Laboratory bioSensor devices that analyse complex compounds;
• Searches with multiple bioSensors (accelerated and strengthened by the uniform and well determined liquid flow rate in each parallel micro camera).

Advantages

• Accurate, predetermined and uniformly distributed amount of liquid in the biosensor micro-cameras;
• Enhanced contact of the functional liquid with biosensor electrodes, allowing better antigens accumulation, electrodes washing  and biosensors restoring of the  for subsequent analysis.